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Kim Philby: The MI6 double agent who spied for Russia

Kim Philby, pictured in 1955, was a Soviet double agent who leaked information from inside MI6 during WWII | Image: Public Domain

From the 1930s right into the era of the Cold War, a group of seemingly patriotic British men consistently betrayed their country by leaking secrets to the Soviet Union. But who exactly were Kim Philby and the Cambridge Five?

Kim Philby

The son of a British diplomat, Kim Philby embraced communism as a Cambridge student in the early 1930s. His connections put him on the radar of a Soviet spymaster named Arnold Deutsch, who instructed him to break off contact with his communist friends in order to penetrate the British establishment.

Successfully posing as a patriot, Philby entered MI6 during the Second World War. As head of counter-Soviet intelligence, Philby was the fox in charge of the hen house, sabotaging the would-be defection of a Soviet agent and helping wreck an Allied operation against communist Albania. But when his friends and fellow Cambridge spies Donald Maclean and Guy Burgess were busted in 1951, the glare of suspicion fell on Philby.

A lack of hard evidence allowed Philby to remain at large. A decade later, a KGB defector confirmed Philby was indeed a Soviet mole. Nicholas Elliott, one of Philby’s closest MI6 friends who’d always believed in his innocence, was tasked with extracting a formal confession. ‘I once looked up to you, Kim,’ Elliott told him. ‘My God, how I despise you now.’

Fearing imprisonment, Philby fled to Moscow rather than cooperate further. Some believe British intelligence permitted him to escape, rather than deal with the public embarrassment of a trial. Philby lived on as a Soviet citizen and national hero until his death in 1988.

Donald Maclean

Like Philby, Donald Maclean came from a prestigious family – his father was not only an MP but served as leader of the opposition. Despite his establishment background, Maclean was an open communist while at Cambridge in the early 30s. Even when he joined the Foreign Office, Maclean openly admitted he hadn’t ‘entirely shaken off’ his communist leanings.

Soon after, his Cambridge friend Kim Philby recommended Maclean as a potential recruit to Arnold Deutsch. Maclean’s serious demeanour and diplomatic connections made him an attractive asset for the Soviet spymaster.

During the war, Maclean passed on US nuclear secrets to the Soviets and carried on leaking information on US/UK relations in the post-war period. Then, coded messages between the US and USSR were intercepted, revealing Maclean’s treachery. Tipped off by Philby, Maclean and his fellow mole Guy Burgess escaped across the Iron Curtain in 1951. Maclean settled seamlessly into his new life in Russia, taking on academic roles until he passed away in 1983.

Guy Burgess

The son of a Royal Navy commander, Guy Burgess was the most charismatic of the Cambridge spies, known for his devilish wit, booze-sodden charm, and devil-may-care attitude. Like Donald Maclean, he was recommended to Arnold Deutsch by Kim Philby. Deutsch was initially sceptical, believing Burgess to be a bit of a liability, but he was eventually recruited as a Soviet spy.

Burgess worked for a time at the BBC, mingling with some of the leading figures of the pre-war period, including Winston Churchill. Burgess later worked for MI6 and the Foreign Office, sending classified information to the Soviet Union during the war and beyond.

Over time, his hard-drinking and promiscuous lifestyle made him a rather notorious figure, and he was deemed a ‘burnt out’ agent by his KGB handlers. When Maclean was exposed by the intercepted Soviet messages, it was decided that Burgess should escape the West alongside him in 1951. He adjusted less well to Soviet life than Maclean and Philby, partly because of his alcoholism, and died in 1963.

Anthony Blunt

A renowned art historian who, for decades, was responsible for overseeing the Royal Family’s immense collection of paintings, drawings and other artworks, Anthony Blunt was one of the most eminent cultural figures of his time. He was also a Soviet spy, having embraced communism while at Cambridge in the 1920s.

Blunt may have been recruited by Arnold Deutsch through his close friendship with Guy Burgess. At any rate, he proved a rich source of classified information while working for MI5 during the war. Becoming the Surveyor of the King’s (later Queen’s) Pictures in 1945 meant he was less useful as a Soviet asset. However, he did secretly assist in the sudden escape of Maclean and Burgess.

Blunt’s treachery came to light in 1963 when an American acquaintance and fellow communist from his Cambridge days gave the game away to the FBI. Not wanting this shocking story to go public, the British establishment opted to hush things up and give Blunt immunity from prosecution. Public exposure only came much later, in 1979, when Margaret Thatcher named him as a spy in Parliament. Stripped of his knighthood, Blunt died in disgrace in 1983.

John Cairncross

The son of an ironmonger and schoolteacher, John Cairncross didn’t have the lofty, genteel background of the other Cambridge spies. While he was known for his intellect, he was a prickly personality who lacked the easy charm of the likes of Philby and Burgess. However, his contempt for the British system made him another recruitment target and he was approached in the mid-1930s while at the Foreign Office.

During the war, Cairncross leaked Foreign Office and cabinet papers, and even decrypted transcripts created by the codebreakers at Bletchley Park. He later moved to MI6 and came under suspicion when British agents found evidence connecting him with Burgess and Maclean following their defection in 1951.

Public exposure as the ‘fifth man’ only came in the wake of Anthony Blunt being outed in 1979. But, like the others, Cairncross was never prosecuted for spying. He later insisted he was a ‘loner outside’ the Cambridge spy ring, that he was essentially loyal to Britain and only spied to help the Soviets prevail against the Germans in the war. Cairncross died in 1995.